Ancient humans felt the need to explain the world around them, they had no explanation, that's why they created "gods". The wrath of Zeus used to explain why we have thunder, for instance... Now we have science, that explains most of life's events, and in the end, we realized we don't need a god to create the things we see and experience everyday in our lives.

The burden of proof is on the person making the positive claim. You must demonstrate that no god exists.

No specific god is named, so making the argument "no god exists " includes any god(s).

Thus far, you are attempting to prove that any god doesn't exist because people have erroneously attributed natural phenomena to god. Science has attributed towards erroneously theories but this doesn't mean science is wrong.